add textlength and textbbox to ImageDraw

Tests/test_imagefont.py

@@ -221,12 +221,15 @@ class TestImageFont:
             "Tests/fonts/" + font, size, layout_engine=self.LAYOUT_ENGINE
         )
 
+        im = Image.new(mode, (1, 1), 0)
+        d = ImageDraw.Draw(im)
+
         if self.LAYOUT_ENGINE == ImageFont.LAYOUT_BASIC:
-            length = f.getlength(text, mode)
+            length = d.textlength(text, f)
             assert length == self.metrics["getlength"][length_basic_index]
         else:
             # disable kerning, kerning metrics changed
-            length = f.getlength(text, mode, features=["-kern"])
+            length = d.textlength(text, f, features=["-kern"])
             assert length == length_raqm
 
     def test_render_multiline(self):
@@ -813,20 +816,20 @@ class TestImageFont:
         else:
             width, height = (128, 44)
 
+        bbox_expected = (left, top, left + width, top + height)
+
         f = ImageFont.truetype(
             "Tests/fonts/NotoSans-Regular.ttf", 48, layout_engine=self.LAYOUT_ENGINE
         )
 
-        # test getbbox
-        assert f.getbbox(text, anchor=anchor) == (left, top, left + width, top + height)
-
-        # test render
         im = Image.new("RGB", (200, 200), "white")
         d = ImageDraw.Draw(im)
         d.line(((0, 100), (200, 100)), "gray")
         d.line(((100, 0), (100, 200)), "gray")
         d.text((100, 100), text, fill="black", anchor=anchor, font=f)
 
+        assert d.textbbox((0, 0), text, f, anchor=anchor) == bbox_expected
+
         with Image.open(path) as expected:
             assert_image_similar(im, expected, 7)
 
@@ -879,13 +882,24 @@ class TestImageFont:
             pytest.raises(ValueError, lambda: font.getmask2("hello", anchor=anchor))
             pytest.raises(ValueError, lambda: font.getbbox("hello", anchor=anchor))
             pytest.raises(ValueError, lambda: d.text((0, 0), "hello", anchor=anchor))
+            pytest.raises(
+                ValueError, lambda: d.textbbox((0, 0), "hello", anchor=anchor)
+            )
             pytest.raises(
                 ValueError, lambda: d.multiline_text((0, 0), "foo\nbar", anchor=anchor)
             )
+            pytest.raises(
+                ValueError,
+                lambda: d.multiline_textbbox((0, 0), "foo\nbar", anchor=anchor),
+            )
         for anchor in ["lt", "lb"]:
             pytest.raises(
                 ValueError, lambda: d.multiline_text((0, 0), "foo\nbar", anchor=anchor)
             )
+            pytest.raises(
+                ValueError,
+                lambda: d.multiline_textbbox((0, 0), "foo\nbar", anchor=anchor),
+            )
 
 
 @skip_unless_feature("raqm")

Tests/test_imagefontctl.py

@@ -222,10 +222,12 @@ def test_language():
     ids=("None", "ltr", "rtl2", "rtl", "ttb"),
 )
 def test_getlength(mode, text, direction, expected):
-    try:
-        ttf = ImageFont.truetype(FONT_PATH, FONT_SIZE)
+    ttf = ImageFont.truetype(FONT_PATH, FONT_SIZE)
+    im = Image.new(mode, (1, 1), 0)
+    d = ImageDraw.Draw(im)
 
-        assert ttf.getlength(text, mode, direction) == expected
+    try:
+        assert d.textlength(text, ttf, direction) == expected
     except ValueError as ex:
         if (
             direction == "ttb"
@@ -374,6 +376,8 @@ def test_combine_multiline(anchor, align):
     d = ImageDraw.Draw(im)
     d.line(((0, 200), (400, 200)), "gray")
     d.line(((200, 0), (200, 400)), "gray")
+    bbox = d.multiline_textbbox((200, 200), text, anchor=anchor, font=f, align=align)
+    d.rectangle(bbox, outline="red")
     d.multiline_text((200, 200), text, fill="black", anchor=anchor, font=f, align=align)
 
     with Image.open(path) as expected:
@@ -396,14 +400,28 @@ def test_anchor_invalid_ttb():
         pytest.raises(
             ValueError, lambda: d.text((0, 0), "hello", anchor=anchor, direction="ttb")
         )
+        pytest.raises(
+            ValueError,
+            lambda: d.textbbox((0, 0), "hello", anchor=anchor, direction="ttb"),
+        )
         pytest.raises(
             ValueError,
             lambda: d.multiline_text(
                 (0, 0), "foo\nbar", anchor=anchor, direction="ttb"
             ),
         )
+        pytest.raises(
+            ValueError,
+            lambda: d.multiline_textbbox(
+                (0, 0), "foo\nbar", anchor=anchor, direction="ttb"
+            ),
+        )
     # ttb multiline text does not support anchors at all
     pytest.raises(
         ValueError,
         lambda: d.multiline_text((0, 0), "foo\nbar", anchor="mm", direction="ttb"),
     )
+    pytest.raises(
+        ValueError,
+        lambda: d.multiline_textbbox((0, 0), "foo\nbar", anchor="mm", direction="ttb"),
+    )

src/PIL/ImageDraw.py

@@ -385,9 +385,6 @@ class ImageDraw:
         elif anchor[1] in "tb":
             raise ValueError("anchor not supported for multiline text")
 
-        if font is None:
-            font = self.getfont()
-
         widths = []
         max_width = 0
         lines = self._multiline_split(text)
@@ -395,12 +392,8 @@ class ImageDraw:
             self.textsize("A", font=font, stroke_width=stroke_width)[1] + spacing
         )
         for line in lines:
-            line_width = font.getlength(
-                line,
-                self.fontmode,
-                direction=direction,
-                features=features,
-                language=language,
+            line_width = self.textlength(
+                line, font, direction=direction, features=features, language=language
             )
             widths.append(line_width)
             max_width = max(max_width, line_width)
@@ -487,6 +480,148 @@ class ImageDraw:
             max_width = max(max_width, line_width)
         return max_width, len(lines) * line_spacing - spacing
 
+    def textlength(self, text, font=None, direction=None, features=None, language=None):
+        """Get the length of a given string, in pixels with 1/64 precision."""
+        if self._multiline_check(text):
+            raise ValueError("can't measure length of multiline text")
+
+        if font is None:
+            font = self.getfont()
+        try:
+            return font.getlength(text, self.fontmode, direction, features, language)
+        except AttributeError:
+            size = self.textsize(
+                text, font, direction=direction, features=features, language=language
+            )
+            if direction == "ttb":
+                return size[1]
+            return size[0]
+
+    def textbbox(
+        self,
+        xy,
+        text,
+        font=None,
+        anchor=None,
+        spacing=4,
+        align="left",
+        direction=None,
+        features=None,
+        language=None,
+        stroke_width=0,
+    ):
+        """Get the bounding box of a given string, in pixels."""
+        if self._multiline_check(text):
+            return self.multiline_textbbox(
+                xy,
+                text,
+                font,
+                anchor,
+                spacing,
+                align,
+                direction,
+                features,
+                language,
+                stroke_width,
+            )
+
+        if font is None:
+            font = self.getfont()
+        bbox = font.getbbox(
+            text, self.fontmode, direction, features, language, stroke_width, anchor
+        )
+        return bbox[0] + xy[0], bbox[1] + xy[1], bbox[2] + xy[0], bbox[3] + xy[1]
+
+    def multiline_textbbox(
+        self,
+        xy,
+        text,
+        font=None,
+        anchor=None,
+        spacing=4,
+        align="left",
+        direction=None,
+        features=None,
+        language=None,
+        stroke_width=0,
+    ):
+        if direction == "ttb":
+            raise ValueError("ttb direction is unsupported for multiline text")
+
+        if anchor is None:
+            anchor = "la"
+        elif len(anchor) != 2:
+            raise ValueError("anchor must be a 2 character string")
+        elif anchor[1] in "tb":
+            raise ValueError("anchor not supported for multiline text")
+
+        widths = []
+        max_width = 0
+        lines = self._multiline_split(text)
+        line_spacing = (
+            self.textsize("A", font=font, stroke_width=stroke_width)[1] + spacing
+        )
+        for line in lines:
+            line_width = self.textlength(
+                line, font, direction=direction, features=features, language=language
+            )
+            widths.append(line_width)
+            max_width = max(max_width, line_width)
+
+        top = xy[1]
+        if anchor[1] == "m":
+            top -= (len(lines) - 1) * line_spacing / 2.0
+        elif anchor[1] == "d":
+            top -= (len(lines) - 1) * line_spacing
+
+        bbox = None
+
+        for idx, line in enumerate(lines):
+            left = xy[0]
+            width_difference = max_width - widths[idx]
+
+            # first align left by anchor
+            if anchor[0] == "m":
+                left -= width_difference / 2.0
+            elif anchor[0] == "r":
+                left -= width_difference
+
+            # then align by align parameter
+            if align == "left":
+                pass
+            elif align == "center":
+                left += width_difference / 2.0
+            elif align == "right":
+                left += width_difference
+            else:
+                raise ValueError('align must be "left", "center" or "right"')
+
+            bbox_line = self.textbbox(
+                (left, top),
+                line,
+                font,
+                anchor,
+                direction=direction,
+                features=features,
+                language=language,
+                stroke_width=stroke_width,
+            )
+            if bbox is None:
+                bbox = bbox_line
+            else:
+                bbox = (
+                    min(bbox[0], bbox_line[0]),
+                    min(bbox[1], bbox_line[1]),
+                    max(bbox[2], bbox_line[2]),
+                    max(bbox[3], bbox_line[3]),
+                )
+
+            top += line_spacing
+
+        if bbox is None:
+            return xy[0], xy[1], xy[0], xy[1]
+        return bbox
+
 
 def Draw(im, mode=None):
     """